Effects of flaxseed on breast cancer growth

Abstract

The use of flaxseed (linseed) to combat breast cancer has attracted increased attention since the preliminary results of a clinical study were presented in the San Antonio Breast Cancer Symposium in December 2000. One of the most often quoted implications of the study was that the anti-tumour effect of flaxseed muffin may be comparable to that of tamoxifen. However, flax-seed also contains secoisolariciresinol diglycoside (SDG), which is converted by the gut bacteria into the oestrogenic lignans, enterodiol and enterolac-tone. Given that other plant-derived oestrogenic substances (phyto-oestrogens) can stimulate breast cancer growth under certain circusmtances, there are concerns regarding the safety of flaxseed. The following review will look at the existing data to help clarify some of these issues.

Keywords

breast cancer complementary therapies estrogens flax lignans patient education

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